Is leaving the dish washing sponge in used detergent water build up mold?

My roommates are cheap and think that if we dont squeeze the used dish detergent after we wash the dishes and leave it in the dish and reuse. Does anybody know that if it build up mold?Is leaving the dish washing sponge in used detergent water build up mold?
Rinse and squeeze it out every time and let it dry out. At least once a week rinse it out good, get it good and full of clean water, set it on a plate and microwave it for three minutes to kill all the stuff that is growing in there. Let it cool off, rinse again and let it dry. One that's been left to soak is really GROSS!!!Is leaving the dish washing sponge in used detergent water build up mold?
It can sour in the water unless you have added something like a few drops of tea-tree oil, grape-seed extract, silver solution or a little peroxide - all of which kill germs and keep the water and sponge from souring. Even if you wring out the sponge each time, it can sour between washings if some of the above is not used in the water, or on the sponge.
Yuck! I don't know about the mold part, but it just doesn't seem sanitary! :) I always rinse mine in HOT water after doing dishes and then putting in microwave for 5 minutes. Then the sponge is ready to go the for the next day.





I read an article once that suggested doing this, as it is the only ';real'; way to kill all of the germs. It works better than bleach.
That is so nasty. The sponge has pours very big pours. As a capfull of bleach to the water. Nasty bacteria, yuck.